1. Field of the Invention
The present invention relates to a device for mounting a tire utilizing a locking sleeve and, more particularly, a device for mounting a multiple-use tire, i.e. a tire which can be inflated with air (meaning any type of suitabie gas) or deflated to different pressures according to the nature of the ground, on a dismountable type wheel rim consisting, on the one hand, of a rim with a fixed flange, a removable flange and a split ring for holding the removable flange in position against a bead of the tire or, on the other hand, of a two-piece rim secured together.
2. Description of the Prior Art
This mounting relies upon a band or ring for holding and locking the beads of the tire against the flanges of the wheel rim, whatever the tire inflation pressure. Such bands or collars positioned on the rim are known and have the object of limiting collapse in the case of a flat or puncture. Such bands have a thickness greater than the height of the flange of the rim to precisely avoid a complete collapse of the tire on puncture. For example, according to a construction described in French Pat. No. 1,304,992, the locking band is mounted on the rim in the form of a ring applied to the inner surfaces of the beads under prior tension so as to compress the beads against the flanges of the rim. In this tire, the inner tube is not tubular but instead is constituted by a split casing surrounding the locking band, the edges of the split casing being held by gripping between the band and the bottom of the rim.
U.S. Pat. No. 2,339,542 also describes a pressure ring for a tire associated with an inner tube and designed to hold a tire on a rim. However, this ring which is of rubber is compressible and deformable. Since its radial expansion is prevented by metal wires which are incorporated therein, when the tire is inflated and in position on the rim with the wheel disk mounted so as to be clamped on the wheel hub in abutment against the rim, the ring is buttressed or arched so as to have a convex shape. This arching or buckling cancels one of the essential functions of the locking band, which is to prevent rotation of the tire on the rim in use over any surface with an inflation pressure less than normal. The same case applies with the sealing ring or annulus which is the subject of U.S. Pat. No. 2,857,951, which automatically retains an arched shape when the tire is deflated, and which is extendable under the effect of inflating air pressure to increase its radial width until it becomes flat.
In another known device (cf. Applicant's French Pat. No. 2,246,405), which device is intended for tubeless tires, the locking band or collar thereof is also mounted to the rim with pre-tensioning, but its width is greater than the inner separation of the beads of the tire when they are mounted to the flange of the rim.
Applicant has observed after several years of testing that these types of locking sleeves have a major drawback in that they are very expensive insofar as they are accompanied by an imperative need to place them under tension to position them on the wheel rim.